Previous work in this laboratory and others has shown that the inferior temporal cortex is important for the visual processing underlying pattern recognition. Also studies have shown that single neurons in this area of cortex are responsive to visual stimuli. The studies which are underway are an attempt to determine what parameters or features of the stimulus are important in the modulation of the activity of the cells. We have chosen to do the analysis using spatial frequency grating as the probe stimuli because all visual stimuli can be broken down into sine wave gratings, and thus the responses to sine wave gratings can potentially be used to reconstruct the response of single cells to more complex stimuli. The responses are compared to those obtained with stimuli which have been used previously such as bars, slits, and spots, as well as more complex patterns. We hope that by investigating single cell responses in this orderly manner we will be in a position to predict the stimulus parameters which are processed in this region of cortex, and as a result construct fruitful hypotheses regarding the role of inferior temporal cortex in stimulus coding.